1. Technical Field
The invention relates to a vehicle with a controller corresponding to the independent claim. Specifically, it relates to a vehicle suitable for disabled people that is provided with a steering and brake input module on which different exchangeable operating elements for steering and braking the vehicle according to the wish and need of the user can be attached. The invention also relates to a method for subsequently retrofitting a vehicle with a control system.
2. State of the Art
Many input devices for purely electric control systems are known in the state of the art.
In particular, control systems are known which give the driver of a vehicle feedback about the steering power or the wheel position. For this, so-called force feedback systems were developed to fulfill this task. As feedback value, it is possible to use either the steering power effectively generated at the steering gear or the effective wheel steering lock angle. The feedback can in particular occur electronically, mechanically or hydraulically. Force feedback, apart from being used in vehicles, is also used for simulators or computer games. The most important task of the force feedback systems for land-based motor vehicles is to inform the driver about the state of the road, the vehicle lateral acceleration and the road grip reserve of the wheels. In applications for vehicles for physically disabled people, a so-called joystick or sidestick is typically used for entering a control signal.
Such a system is known for example from EP1595766, wherein a vehicle is steered on the basis of actuating a joystick. The control signal is forwarded through a step-down gear to a potentiometer, which then steers an electric motor. This motor is connected through a gearing mechanism with the steering column. Mechanical elements enable the rotation movement to be converted into a linear movement. The linear movement is then mechanically conveyed over wiring harnesses to the joystick, so that the user receives a feedback about the movement. The disadvantage of this system is, however, that it cannot be adjusted to the user.
GB2314607 discloses a further steering system with a joystick. The joystick can be moved in the vehicle's transverse axis. The vehicle can be accelerated or slowed through a foot pedal and a control stick. An actuator affixed to the joystick can exert a reactive force onto the joystick. The disadvantage of this system is that the driver needs to steer the vehicle with his hands and also with his feet. Furthermore, the joystick can be actuated unintentionally, which has a negative impact on the driving safety.
WO2005120929 discloses another joystick. In order to execute a steering movement, the joystick can be actuated circularly in a guide slot. This joystick has the disadvantage that the user needs to move the entire arm, which causes fatigue symptoms to the driver especially on long journeys.
The handling of so-called four-way joysticks is furthermore very difficult to learn for the user. This is because the joystick must be pressed forwards to accelerate the vehicle and additionally the joystick needs to be moved to the right or to the left in a curve. This is a disadvantage, since it is easily possible due to uncontrolled movements to lose control over the vehicle with a joystick of this kind.
A further problem with input devices from the state of the art arises from the mechanical factors that often require a considerable overall size.
A further disadvantage of the known input aids is that the user is limited to the proposed control system, the integrated joystick, etc. For this reason, US20040140145 for instance proposes a common electronics assembly, to which the different control systems can be connected. This will admittedly afford modularity to the system. The user can thus select from a plurality of control systems the one that appears most comfortable for him and have it built into his vehicle. In this system, however, the entire control system unit is replaced. This is comparatively laborious. If the user then decides to choose another system, there is no simple possibility of switching from a joystick to a slide controller or a steering wheel. In certain circumstances, it may be necessary even to replace the entire seat. Furthermore, in this modular system, steering and braking can only be replaced in combination, which constitutes a further disadvantage. The user who can yet still steer but no longer brake (for example because of a disability in the legs) can only select the complete system, not just a module for the brakes. This increases the overall cost of the system and makes it more complicated and less attractive for disabled people.